/Engine/Plugins/Runtime/nDisplay/Source/DisplayCluster/Public/DisplayClusterPlayerInput.h
This one is nDisplay specific implementation. It's responsible for replication of UE native input within a cluster to support simulation determinism. Various input sync policies might be implemented here.
[UCLASS](Programming/UnrealArchitecture/Reference/Classes#classdeclaration)(Within=PlayerController, Config=Input, Transient) class UDisplayClusterPlayerInput : public [UEnhancedPlayerInput](API\Plugins\EnhancedInput\UEnhancedPlayerInput)